Electric safety



(No Model.)

' 2 SheetsSneet 1 C. W. BALDWIN.

ELECTRIC SAFETY APPARATUS FOR ELEVATORS. No. 263380.

2.. Mia

Patented Aug. 29, 1882? a (TA? '-Jviz/ 1 I '(No Model.)

0. W. BALDWIN.

ELECTRIC SAFETY APPARATUS FOR ELEVATORS. LNG, 263,380. I Patented Aug. 29, 1882.

2 Sheets-Sheet; 2.

.Uwt'rao STATES PATENT @rrica.

ovens BALDWIN, on oi'i'ioaco, liminois.

ELECTRIC SAFETWAPPARATUS FOR ELEVATORS;

SPECIFICATION forming part of Letters Patent No. 263,380, dated August 29, 1882.

Application filed April 1882. (No model.)

To all whom it mag/ concern:

13s it known that I, CYRUS W. BALDWIN, a citizen of the United States, and aresident of Chicago, Cook county, Illinois, have. invented 5 certain Improvements in Electric Safety Apparatus for Elevators, of which the following is a specification. Y

My invention has for its object to prevent accidents liable to result from thederangement ot the machinery of elevators or hoists; and it consists in combining with the mechanism and with the braking or safety appliances a governor and an electrical detent, whereby upon injury to any part of the apparatus resulting in an undue increase in the speed of the cage the governor is caused to-break the circuit, the detentis relea-sed,and the brakes are caused to 'be applied, arresting the further motion ofthe cage.

I will now describe certain apparatus illustrating my invention, although I wish it to be understood that I do not limit myself to the special appliances set forth.

In the drawings, Figure 1 represents in ele- 5 vation part of an ordinary elevator, A being the cage, supported by a cable, L, and provided with suitable brakes, O C, constructed to be applied or removed on theturningofasbaft carrying a drum, 7:, orotherwise. Fig. 2 is a part-sectional elevation, and Fig. is an in verted plan.

(J U are the brake-levers, each .onnected by rodsj to a piston, m, in a cylinder, I, to which air is admitted under pressure from a pumping or com pressing apparatus, N, as fully described in the Letters Patentgranted to me. Acockm, connected to the drumshaft F, serves to regulate the iiow of air between the pump and cylinder. liound the drum is wound a rope, I), which extends to the top of the well and over the grooved pulley of agovernor, E, which carries arms 0, retracted .by springs f, and ca'pable of being thrown out by centrifugal action when the cage and governor attain undue speed. Below the pulley is pivoted a lever, c, which constitutes the circuit-breaker of an electrical circuit extending between abattery, N, andau electro-inagnet, P, the armature of which is a loose cylinder, '10. The rope I) carries a weight, W,at its freeend, and passes through a funnelshapcd recess, .r. in a bracket, 1t, carrying the electro-maguet P, the said recess being wide enough to permit the rope to travel freely, and the magnet being so arranged that when the armature is released it will fall between the rope and the inclined face of the recess. So long as the cage travels at its proper rate of speed the parts retain the positions shown; but any derangement of any part of the diachinery resultingin any undue increase ofmotion throws out the arms 0 of the governor, one of which strikes the lever a,vibrates it, breaks the eircuit,thus demagnetizing the magnet P, and the armature then falls, and byjamming between the side of the recess w and the rope -b clamps the latter, so that the drum is is turned and the brakes applied by the admission of air to the cylinder I.

A most important feature of my invention is the use of a governor having a movement coincident with but independent of that of the cage and independent of the circuit-breaker, whereby the governormay be made so extremely sensitive as to act upon the circuitbreaker upon the slightest increa-sein the speed of the cage beyond that at which it should travel, or in fact at any speed, normal or otherwise, according as the governor is set. My device differs in this respect from those in which the circuit-breaker is' the governor, in which the breaking of the circuit depends upon the actual speed of the cage itself, and not upon that of an independent governing device.

My invention is not limited to battery-currents, but; may be used with magneto-currents generated by the movements of the elevator mechanism or by some extraneous power.

The governor and circuit-breaker operated thereby may be employed in connection with various brake or retarding devices; and it will be apparent that the structure of thedetent will depend to a great degree upon the appliances with which it is used.

I am aware that electric conductingwires have been combined with electro-magnets upon a cage to release the catches upon the breaking of said wires. My invention is distinguished frointhis by the combination, with the electro-magnet, of a governor driven from some part of the apparatus, and devices which break the circuit upon the acceleration of the speed, thus arresting the cage when it moves too rapidly from any cause, whether the rupture of the suspensories or the slipping of a belt, or from any otherdisarrangeinent of the mechanism.

1. The combination, with an elevator, of a governor driven with a positive movement from sonic moving part of the mechanism, devices, as described, whereby the in'ovementof the cage may he arresred, a detent constructed to be held out of operation during the completion of an electrical current, and a circuitbreaker independent of the governor, and constructed to be operated thereby to release the detent upon an increase in the speed at which the governor is driven, as setvforth. V

2. The combination, with a rope supplemental to the hoisting-cable and" the brake of an elevator, oi? a detent constructed to beheld out of action by an electric current, a circuithreaker, and a governor constructed to operate the circuit-breaker on an undue increase of 20 speed, as specified.

3. The. combination of the cage, its brakes and operating-rope I), a governor, a bracket I having a contracting opening, as, for the passage of said rope, a circuiobreaker arranged to be operated by the governor, and an electroniagnet having an armature constituting a detent and arranged to be held above said opening an by the magnet, substantially as set forth. In testimony whereof I have signed ny name to this specification in the presence of two subscribing witnesses. CYRUS \V. BALDWIN.

Witnesses:

HENRY L. KENT, HOLMES Hoes. 

